Publication Date:
2003
Description:
A global set of present plate boundaries on the Earth is presented in
digital form. Most come from sources in the literature. A few boundaries are newly
interpreted from topography, volcanism, and/or seismicity, taking into account relative
plate velocities from magnetic anomalies, moment tensor solutions, and/or geodesy. In
addition to the 14 large plates whose motion was described by the NUVEL-1A poles
(Africa, Antarctica, Arabia, Australia, Caribbean, Cocos, Eurasia, India, Juan de Fuca,
Nazca, North America, Pacific, Philippine Sea, South America), model PB2002 includes 38
small plates (Okhotsk, Amur, Yangtze, Okinawa, Sunda, Burma, Molucca Sea, Banda Sea,
Timor, Birds Head, Maoke, Caroline, Mariana, North Bismarck, Manus, South Bismarck,
Solomon Sea, Woodlark, New Hebrides, Conway Reef, Balmoral Reef, Futuna, Niuafo'ou,
Tonga, Kermadec, Rivera, Galapagos, Easter, Juan Fernandez, Panama, North Andes,
Altiplano, Shetland, Scotia, Sandwich, Aegean Sea, Anatolia, Somalia), for a total of 52
plates. No attempt is made to divide the Alps-Persia-Tibet mountain belt, the Philippine
Islands, the Peruvian Andes, the Sierras Pampeanas, or the California-Nevada zone of
dextral transtension into plates; instead, they are designated as "orogens" in which
this plate model is not expected to be accurate. The cumulative-number/area distribution
for this model follows a power law for plates with areas between 0.002 and 1 steradian.
Departure from this scaling at the small-plate end suggests that future work is very
likely to define more very small plates within the orogens. The model is presented in
four digital files: a set of plate boundary segments; a set of plate outlines; a set of
outlines of the orogens; and a table of characteristics of each digitization step along
plate boundaries, including estimated relative velocity vector and classification into
one of 7 types (continental convergence zone, continental transform fault, continental
rift, oceanic spreading ridge, oceanic transform fault, oceanic convergent boundary,
subduction zone). Total length, mean velocity, and total rate of area
production/destruction are computed for each class; the global rate of area production
and destruction is 0.108 m 2 /s, which is higher than in previous models because of the
incorporation of back-arc spreading
Keywords:
Plate tectonics
;
Modelling
;
map
;
Crustal deformation (cf. Earthquake precursor: deformation or strain)
;
Geodesy
;
Paleomagnetism
;
G3
;
G-cubed
;
AGU
;
3040
;
Marine
;
Geology
;
and
;
Geophysics:
;
Plate
;
tectonics
;
5475
;
Planetology:
;
Solid
;
Surface
;
Planets:
;
Tectonics
;
8150
;
Tectonophysics:
;
Evolution
;
of
;
the
;
Earth:
;
Plate
;
boundary--general
;
8158
;
Evolution
;
of
;
the
;
Earth:
;
Plate
;
motions--present
;
and
;
recent
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